Another research-aid tool that should get even more spotlight than it does, is citation guides. Citation guides make sense of the most prominent, but immensely obscure elements of legal identifiers: citations. The main identifier for legal information is a condensed citation. Earlier in this book you came across citations of both secondary and primary sources. 16 TOURO L. REV. 25 and 40 C.F.R. Section 72.2 (2002) represent such legal citations. The first one identifies a law review articles. The second one identifies an administrative regulation. They use specific rules of citations, whose purpose are briefly mentioned below.

The Identifying Role of Legal Citations
• identify the type of the document, whether it is a primary or secondary source
• within that typology, what hierarchical place it occupies (whether it is a case, statute, or an administrative regulation).

For example, the “16 TOURO L. REV.25” refers to a secondary source. More precisely it identifies an article that was published in the 16th volume of the Touro Law Review at page 25. reading 40 C.F.R. Section 72.2 (2002) tells the researcher that the document is a primary source. C.F.R stands for The Code of Federal Regulations, a codification of all federal rules and regulations broken down by subject matter. The number that precedes the abbreviation, “40” indicates the title of the C.F.R to which the administrative regulation relates (e.g., title 40 concerns environmental protection), while the number that follows the abbreviation, “72.2,” indicates the section number of the regulation. The year, “2002,” is the last time that regulation was updated. Thus, although you may not know its name, you know its address, so it will be easy to locate once you choose the repository of administrative regulations you want to use: in print or online.

Unlike any other citation rules, legal citation incorporates a lot of substantive legal knowledge. It both conveys knowledge to the reader and lives on assumed knowledge. This double cognitive role enables legal citations to perform an additional function: they signal the reader how much value the source they are consulting has in their legal research process. The more the reader knows about primary and secondary sources, the more information the reader extracts from the citation. A law review article is as important as the publication it carries it. An administrative regulation is as important as the statute enabling it or the opinion referring to it.

There are a few sources that would help you make sense of any legal citation. Peter Martin’s Introduction to Basic Legal Citation is easily accessible online. However it is not meant to be comprehensive. It does not cover the meaning of every single abbreviation of American law sources: either primary or secondary.

On the other hand, Bieber’s Dictionary of Legal Abbreviations, edited by Mary M. Price, assistant director of the Law Library at Vanderbilt Law School, and available on Lexis, provides extensive coverage of all legal abbreviations within the U.S. legal system. It thus helps you understand the abbreviations for titles, terms, and names used in American legal literature.
The legal academe relies on the citation rules contained in The Bluebook: A Uniform System of Citation. All legal scholarship uniformly relies on the Bluebook rule. In addition to citation rules, the Bluebook is also useful because it lists all federal and state primary sources, and identifies them both by their full title and their legal abbreviations. For example, if you are interested in learning the name of the repositories that cover the Supreme Court decisions, all you need to do is go to the section of the Bluebook called the “Table on United States Jurisdiction” (T.1) and search for the names of the Supreme Court reporters. In addition to their names, you will also learn the time frame covered. For example, just by using the Bluebook, you find out that the name of one of the reporters is the United States Reports, that it covers all opinions starting with those decided in 1790, and that its abbreviation is “U.S.”